Option c is the correct answer. Manav, while planning to visit all UNESCO World Heritage Sites in Delhi, will be visiting Red Fort, Qutab Minar, and Humayun Tomb. The three UNESCO World Heritage Sites in Delhi are: Qutub Minar and its Monuments, a complex of structures built in the 12 th and 13 th centuries, including the 72.5 m high red sandstone tower of Qutub Minar, the Quwwatu'l-Islam Mosque, the Alai-Darwaza Gate, and the Iron Pillar of Delhi. Humayun's Tomb, a garden-tomb built by the widow of the Mughal Emperor Humayun in 1562, and considered as the precursor of the Taj Mahal. Red Fort, a fort and palace complex built by the Mughal Emperor Shah Jahan in 1639, and a symbol of Mughal power and architecture.